Several working tasks, for example in production, comprise rather complex working steps as well as other working steps which are not as demanding. Whilst the non-demanding working steps typically are suitable to be automated by robots, the complex working steps are not necessarily accessible for automation by robots. Robot systems for human robot collaboration are known which take advantage of robot automation in those cases also, wherein the complex working steps are performed by a human worker and the non-demanding working steps are performed by a robot in a collaborative task.
Typical industrial robots have a rated power of several kilowatts and endanger every person in their working range therewith when in operation. Thus for non-collaborative robot systems safety mechanism are foreseen, which cause an emergency stop of the robot when a person is entering a safety area around the robot. Robot systems for collaborative robot applications on the other hand require the presence of a human worker within the working range of the robot, for example to hand over a work piece or such. To ensure the safety of the human worker in those cases also, different security approaches are known. One possibility is to use an inherently safe robot, which is not able at all to harm a human worker due to a limited rated power for example. Other possibilities consist in reducing the movement speed of the robot to a safe level or in installing a vision system for detecting critical situations and preventing them accordingly.
Present collaborative robot application systems as such, even though they are correctly designed according to risk assessment, may still be experienced as unpleasant by the human worker and do not consider the individual comfort level of a human. Some human workers might have a certain anxiety if the robot performs a fast movement, other human workers might feel uncomfortable when the robot is moving at a rather close distance to them. Also, a certain pose of a robot might be perceived as threatening by a human worker. The comfort level of the collaborative human worker is reduced therewith dependent on his individual sensation.
Disadvantageous within this state of the art is that a reduced comfort level might lead to serious health problems of the collaborative human worker over the time, for example. But also an increased error rate or a reduced working speed of the human during work might be the result.